* Dollar index slips by nearly 5 pct

* Platinum off 8-1/2 month low

(Updates throughout, adds LONDON dateline)

By Zandi Shabalala

LONDON, Nov 15 (Reuters) - Gold edged higher on Tuesday, snapping a three-session losing streak, on uncertainty over the effects of policies promised by U.S. President-elect Donald Trump and expectations of higher interest rates in December.

Spot gold XAU= added 0.5 percent to $1,226.06 an ounce by 1008 GMT, having slipped on Monday to its lowest since June 3 at $1,211.08.

U.S. gold futures GCcv1 climbed 0.2 percent to $1,224.30.

Trump has vowed to boost domestic spending, which has the potential to stoke inflation, but the market is seeking more detail on his policies.

"Gold is taking back some of the negativity that we have seen over the past week. Although investors are becoming more risk-on, there is still a lot of uncertainty surrounding economic policy in the United States," said ETF Securities commodities strategist Martin Arnold.

"There have been lots of statements of U.S. policy, but we don't have details and we don't know what it looks like. That's fertile ground for gold."

Generally, investors pile into safe-haven assets such as gold in times of political and economic uncertainty.

Gold has shed nearly 9 percent from a Nov. 9 high of $1,337.40 after Trump's election victory, hurt by a stronger U.S. dollar and surging Treasury yields.

"(Market) sentiment is being compounded by the very high probability of the U.S. Fed raising interest rates in December," Arnold said.

Dallas Fed President Robert Kaplan suggested on Monday that the U.S. central bank is on track to raise rates soon.

Gold is highly sensitive to rising rates, which lift the opportunity cost of holding non-yielding assets such as bullion while boosting the dollar, in which it is priced.

Also boosting gold was a near-5 percent fall in the dollar index's .DXY , which measures the greenback against six other leading currencies. The index dropped from 11-month highs to 99.663. FRX/

Among other precious metals, silver XAG= was up 0.8 percent at $17.02 an ounce, having touched its lowest since June 8 at $16.61 in the previous session.

Platinum XPT= rose 0.9 percent to $939.75, bouncing back from the more than eight-month low of $917.50 touched on Monday.

Palladium XPD= was down 0.9 percent at $704, having earlier hit its highest since Oct. 4 at $702.50.

(Additional reporting by Apeksha Nair in Bengaluru; Editing by David Goodman) ((zandi.shabalala@thomsonreuters.com; +44 207 542 5937; Reuters Messaging: zandi.shabalala.thomsonreuters.com@reuters.net))